Table 18. Fetal brain mass models (g vs. fetal mass in g for power law models, g vs. gestational age in weeks for all other models).

Model	${\widehat{\mathit{\theta }}}_0$	${\widehat{\mathit{\theta }}}_1$	${\widehat{\mathit{\theta }}}_2$	${\widehat{\mathit{\theta }}}_3$	$\mathcal{l}\left(\widehat{\mathit{\theta }}\right)$	AIC
Linear Growth	2.9256	—	—	—	-21528.2	43058.5
Quadratic Growth	-3.9135	0.32870	—	—	-11008.6	22021.2
Cubic Growth	-2.1208	0.15645	0.0034746	—	-10927.7	21861.4
Gompertz	0.015740	0.70707	0.064827	—	-10943.7	21893.5
Logistic	462.90	0.19240	32.321	—	-11074.2	22154.4
Power Law	0.35659	0.85318	—	—	-10970.6	21945.2
Luecke Power Law	0.93210	0.55821	0.021936	—	-10956.8	21919.6

For each model considered, the maximum likelihood parameter estimates ($\widehat{\theta }$), log-likelihood ($\mathcal{l}\left(\widehat{\theta }\right)$), and AIC are provided. The row describing the selected model is shown in boldface.